Organic light emitting apparatus and method of producing the same

ABSTRACT

Provided are an organic light emitting apparatus for use in, for example, a flat device display, and a method of producing the apparatus. The organic light emitting apparatus has sides formed by division at ends of its substrate. Three-dimensional portions are formed on the surface of the substrate along the sides. An inorganic sealing layer is formed to extend toward the three-dimensional portions.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an organic light emitting apparatus foruse in, for example, a flat device display, and a method of producingthe apparatus.

2. Description of the Related Art

An organic light emitting apparatus having an organicelectroluminescence (EL) device as a self light emitting device has beenrecently attracting attention because of its potential to serve as aflat device display. The organic EL device is obtained by laminating atleast a first electrode, a stack layer including an organic lightemitting layer, and a second electrode in the stated order on asubstrate. The organic EL device is liable to cause the deterioration ofits properties owing to moisture or oxygen; a trace amount of moisturepeels the stack layer off of an electrode layer, and the peeling isresponsible for the occurrence of a dark spot. In view of the foregoing,the organic EL device is covered with an etching glass cover, a sealingagent is stuck to the periphery of the resultant, and the inside of theresultant is mounted with a moisture absorbent so that moistureinfiltrating from a sealing surface is absorbed by the moistureabsorbent. As a result, the lifetime of the organic EL device issecured.

The realization of a thin, space-saving flat device display using theorganic EL device requires a reduction in space of the moistureabsorbent around a light emitting area. An example of a method ofsealing the organic EL device while eliminating the need for themoisture absorbent is a method involving laminating a sealing layer onthe second electrode. A high-performance sealing layer for preventingmoisture or oxygen from infiltrating into the stack layer is requested.

A silicon oxynitride film obtained by a CVD method or a sputteringmethod, or a sealing layer obtained by laminating ceramic and an organicfilm has been specifically proposed as a sealing layer for an organic ELdevice. Moisture or oxygen can be shielded by using any one of thosesealing layers each formed of an inorganic material for an organic lightemitting layer.

By the way, in the production of an organic light emitting apparatushaving such organic EL device, from the viewpoint of a reduction inproduction cost, plural organic light emitting apparatuses are producedon a large substrate, and then division (separation) is performed.

Each of the following proposals has been made as a method of dividingindividual organic light emitting apparatuses from a large substrate onwhich plural organic light emitting apparatuses are formed.

Japanese Patent No. 3,042,192 describes the following invention:scribing and breaking are sequentially performed from both surfaces of abonded substrate in the division of the substrate so that damage to thesubstrate in a dividing step is reduced.

Japanese Patent Application Laid-Open No. 2003-181825 describes thefollowing invention: upon production of organic light emittingapparatuses by plural patterning, a pressure transmitting portion fortransmitting a pressure in a breaking step from one substrate to theother substrate is formed, whereby a problem of defective sectioning ofthe substrate can be solved.

However, when individual organic light emitting apparatuses are dividedby employing a general scribing approach from a substrate on whichplural organic light emitting apparatuses are formed, the peeling orcracking of a sealing layer occurs at a position where the apparatus isto be divided. As a result, moisture or a gas component infiltrates intoa stack layer, thereby leading to the deterioration of display. None ofJapanese Patent No. 3,042,192 and Japanese Patent Application Laid-OpenNo. 2003-181825 describes measures for a reduction in occurrence of thepeeling and cracking of a sealing layer formed of an inorganic materialat a position where the apparatus is to be divided.

The present invention has been made in view of the above-mentionedproblems, and an object of the present invention is to provide anorganic light emitting apparatus that can be divided without receivingdamage to a sealing layer such as peeling or cracking in a step ofdividing individual organic light emitting apparatuses from a substrateon which plural organic light emitting apparatuses are formed, and amethod of producing the apparatus.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided thefollowing organic light emitting apparatus as means for solving theabove-mentioned problems of the prior art.

That is, an organic light emitting apparatus obtained by dividing pluralorganic light emitting apparatuses that are integrally formed includes:a substrate having at least a base material, the substrate having sidesformed by dividing the substrate at its ends, and the substrate havingthree-dimensional portions formed on its surface along the sides; anorganic light emitting device formed on the substrate, the organic lightemitting device having a first electrode, an organic light emittinglayer, and a second electrode in the stated order on the substrate; andan inorganic sealing layer formed to cover an upper portion of theorganic light emitting device and the surface of the substrate and toextend toward the three-dimensional portions.

According to another aspect of the present invention, there is providedthe following method of producing an organic light emitting apparatus.

That is, there is provided a method of producing an organic lightemitting apparatus, the organic light emitting apparatus having asubstrate, an organic light emitting device having a first electrode, anorganic light emitting layer, and a second electrode formed in thestated order on the substrate, and an inorganic sealing layer formed tocover an upper portion of the organic light emitting device and asurface of the substrate and to extend toward an end of the substrate,the method including the steps of: forming the organic light emittingdevice having the first electrode, the organic light emitting layer, andthe second electrode in the stated order on the substrate; forming athree-dimensional portion along a division line set in advance on thesurface of the substrate; forming the inorganic sealing layer in thedivision line from above the second electrode so that the inorganicsealing layer straddles the three-dimensional portion; and dividing thesubstrate and inorganic sealing layer along the division line.

According to the present invention, individual organic light emittingapparatuses can be divided without causing damage to a sealing layersuch as peeling or cracking in a step of dividing individual organiclight emitting apparatuses from a substrate on which plural organiclight emitting apparatuses are formed. As a result, it can preventmoisture or a gas component from infiltrating into a stack layercompletely, whereby an organic light emitting apparatus having a longlifetime in which the deterioration of light emission is suppressed canbe obtained.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are sectional views each schematically illustrating anexample of an embodiment of an organic light emitting apparatus of thepresent invention.

FIG. 2 is a perspective view illustrating an example of the shape andplacement position of a three-dimensional portion of the organic lightemitting apparatus of the present invention.

FIG. 3 is a perspective view illustrating another example of the shapeand placement position of the three-dimensional portion of the organiclight emitting apparatus of the present invention.

FIGS. 4A and 4B are perspective views each illustrating another exampleof the shape and placement position of the three-dimensional portion ofthe organic light emitting apparatus of the present invention.

FIGS. 5A and 5B are sectional views each schematically illustrating theshape of the three-dimensional portion of the organic light emittingapparatus of the present invention.

FIG. 6 is a sectional view schematically illustrating a positionalrelationship between the three-dimensional portion of the organic lightemitting apparatus of the present invention and a resistance wire.

FIGS. 7A, 7B, 7C and 7D are sectional views each schematicallyillustrating an example of a method of producing an organic lightemitting apparatus of the present invention.

FIGS. 8A and 8B are sectional views each schematically illustrating anexample of the shape, placement position, and division position of eachof adjacent three-dimensional portions of the organic light emittingapparatus of the present invention.

FIGS. 9A and 9B are sectional views each schematically illustrating theoutline of the constitution of an evaluation substrate in Example 1.

FIG. 10 is a sectional view schematically illustrating the outline ofthe constitution of an evaluation substrate in a comparative example.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, an embodiment of the present invention will be describedwith reference to the drawings. It should be noted that each of thosedrawings schematically illustrates an example of the constitution of anorganic light emitting apparatus according to the present invention bytaking part of the constitution.

FIGS. 1A and 1B are schematic sectional views each illustrating part ofan organic light emitting apparatus for illustrating an example of adevice constitution. The figures each illustrate a range from an end ofa display region to the peripheral region of the region. The lightemitting apparatus illustrated in each of FIGS. 1A and 1B has sidesformed by the division of a substrate at its ends.

A layer (source/drain electrode layer) 2 for constituting a thin filmtransistor (hereinafter referred to as “TFT”), an insulating layer 3,and an organic leveling layer 4 are laminated and formed in the statedorder on a glass base material 1. In this embodiment, the aboveconstitution is adopted as a substrate. Then, a first electrode 5 of aunit pixel is formed on the upper portion of the substrate, and theperiphery of each pixel is covered with a device isolation film 8 madeof polyimide. A stack layer (organic compound layer) 6 is formed bysequentially laminating a hole transporting layer, an organic lightemitting layer, an electron transporting layer, and an electroninjecting layer on the glass base material 1. A second electrode 7 isformed on the upper portion of the structure. Then, the first electrode5, the stack layer 6 including the organic light emitting layer, and thesecond electrode 7 form an organic EL device. Further, a sealing layer 9formed of an inorganic material for completely covering the secondelectrode 7, the stack layer 6, the device isolation film 8, and theorganic leveling layer 4 except an extraction electrode is formed. Then,a circular polarizer 11 is provided for the upper portion of theresultant including the sealing layer 9 through an adhesive 10.

In this embodiment, the substrate has only to have at least the basematerial 1. This is because the present invention is applicable to notonly an active matrix type light emitting apparatus having a thin filmtransistor for driving an individual organic EL device as describedabove but also a passive matrix type light emitting apparatus in whichlight emission is obtained at a portion of intersection of stripe-shapedelectrodes. In the latter apparatus, the substrate has no thin filmtransistor, and an electrode is formed on the base material 1 in somecases.

In addition, in this embodiment, the layer 2 for constituting a TFT is alayer identical to a source/drain electrode. The layer 2 may be a layerdifferent from a source/drain electrode. For example, the layer 2 may bea layer identical to a gate electrode layer.

In addition, the stack layer 6 has only to have at least an organiclight emitting layer; the structure desirably has a hole transportinglayer, an electron transporting layer, and an electron injecting layeras described above.

In the constitution illustrated in FIG. 1A, a three-dimensional portionA having a concave structure is formed in the layer 2 for constituting aTFT and the insulating layer 3 for covering the TFT along a side formedby the division of the substrate, and the end of the sealing layer 9 tobe formed is determined by the three-dimensional portion A. In theconstitution illustrated in FIG. 1B, a three-dimensional portion Ahaving a convex structure is formed on the insulating layer 3, and theend of the sealing layer 9 to be formed is determined by thethree-dimensional portion A. It should be noted that thethree-dimensional portion A formed to have a predetermined depth in thedirection toward the base material 1 from the surface on which theinsulating layer 3 is formed has a concave structure, while thethree-dimensional portion A formed to have a predetermined height in thedirection opposite to the base material 1 from the surface on which theinsulating layer 3 is formed has a convex structure.

The three-dimensional portion A of the present invention is formed onthe periphery of a display region in order that the crack or filmquality discontinuous region of the sealing layer 9 may be generated atthe position where the three-dimensional portion A is formed. Thethree-dimensional portion A is formed so as to be parallel to at leastone side of the display region. Specifically, as illustrated in FIG. 2,the three-dimensional portions A are formed on two sides except the sideon which a power source and a signal supply pad 14 are formed and a sideopposed to the side. Alternatively, as illustrated in FIG. 3, thethree-dimensional portions A are formed on two adjacent sides. Inaddition, as illustrated in each of FIGS. 4A and 4B, the plural trainsof, or plural, three-dimensional portions A are formed on the peripheryof a display region so as to be parallel to one side of the displayregion. Of course, the three-dimensional portions A may be formed on allfour sides so as to surround the display region. In this case, eachthree-dimensional portion A is desirably formed into a line shape with apredetermined pitch between the portion and the display region. However,how to place the portions is not particularly limited as long as a crackor a film quality discontinuous region can be generated in the sealinglayer 9 upon division of an organic light emitting apparatus. Forexample, as illustrated in FIG. 3, an organizational structure formed ofthe three-dimensional portions A each of which is shorter than a certainside of the display region may be formed. When a resin layer is formedon the periphery of the display region, each three-dimensional portion Ais formed in the outer peripheral region of the resin layer.

As illustrated in each of FIGS. 5A and 5B, the shape of eachthree-dimensional portion A may have a concave structure or a convexstructure. Each three-dimensional portion A has only to have a shapewith which the crack or film quality discontinuous region of the sealinglayer 9 can be obtained upon division of an organic light emittingapparatus. A desirable shape will be described with reference to each ofthe outline sectional views of FIGS. 5A and 5B. A height or depth D ofeach three-dimensional portion A is desirably 0.1 μm or more, or onehundredth or more of the thickness of the sealing layer 9. When theheight or depth D of each three-dimensional portion A is less than 0.1μm, or less than one hundredth of the thickness of the sealing layer 9,the three-dimensional portion A is excessively small as compared to thesealing layer 9. As a result, a crack or film quality discontinuity tobe formed at the initial stage of the formation of the sealing layer 9is filled or uniformized in the course of the overlapping of films.Accordingly, individual organic light emitting apparatuses cannot bedivided unless a large external impact is applied to the sealing layer9, with the result that damage such as peeling or cracking occurs inassociation with the division.

A taper angle E of each three-dimensional portion A is not particularlylimited as long as a crack or film quality discontinuity can begenerated in the sealing layer 9. The maximum value for the angle isdesirably 10° or more, and, furthermore, is desirably 45° or more. Themaximum value may be 90° or more. In addition, all the three-dimensionalportions A to be formed on the base material 1 do not need to have thesame taper angle. For example, when plural three-dimensional portions Aare formed on the periphery of a display region, the taper angles ofadjacent three-dimensional portions A and A can be made different fromeach other.

A width G of each three-dimensional portion A is not particularlylimited as long as the width allows the three-dimensional portion A tobe certainly formed. However, the width is desirably as small aspossible because a large width leads to the expansion of a frame region.The width of each three-dimensional portion A is desirably smaller thanthe height or depth D of the portion.

When plural three-dimensional portions A are formed, a pitch F betweenadjacent three-dimensional portions A and A does not need to beconstant, and can take an arbitrary value; provided, however, that thepitch F larger than the height or depth D of each three-dimensionalportion A is desirable because the case where the pitch F is excessivelysmall results in the occurrence of the case where a crack penetratingthrough the sealing layer 9 or film quality discontinuity cannot beobtained.

With the aid of each three-dimensional portion A, the crack or filmquality discontinuous region of the sealing layer 9 to be generated upondivision of individual organic light emitting apparatuses allows thesealing layer 9 to be easily divided by applying a small external impactat the position where the three-dimensional portion A is formed.Alternatively, selecting the shape of each three-dimensional portion Aallows the formation of the sealing layer 9 completely sectioned at theposition where the three-dimensional portion A is formed without theapplication of an external impact.

Examples of a method of forming each three-dimensional portion A includea method involving forming a concave structure or a convex structure byetching and a method involving forming a convex structure by mask filmformation. Each portion is desirably formed by etching in the case ofsuch active matrix type light emitting apparatus as illustrated in FIG.1A. This is because each three-dimensional portion can be formedsimultaneously with a patterning step upon production of a TFT.According to the method, each three-dimensional portion can be easilyformed while a production cost is suppressed.

Further, for example, as illustrated in FIG. 6, a resistance wire 12 canbe provided along each three-dimensional portion A in order that thesealing layer 9 may be certainly sectioned at the crack or film qualitydiscontinuous region of the sealing layer 9 formed by thethree-dimensional portion A. A current is flowed into the resistancewire 12 so that the three-dimensional portion A is heated. As a result,a strong stress is generated in the sealing layer 9, whereby the sealinglayer 9 is sectioned at the crack or film quality discontinuous regionof the sealing layer 9. The resistance wire 12 is not particularlylimited as long as the three-dimensional portion A can be heated byflowing a current into the wire; the wire is desirably formed bypatterning by using the layer for constituting a TFT simultaneously withthe formation of the conductive layer.

The first electrode 5 is not particularly limited as long as it is madeof an electrode material having high conductivity. For example, Cr, Al,or Ag as a material having a high reflectivity can be used. Atransparent electrode such as ITO or IZO may be laminated and used.

The second electrode 7 is not particularly limited as long as it is madeof an electrode material having high conductivity. For example, theelectrode is formed of a highly transmissive or semi-transmissivematerial; an oxide film containing in such as ITO and IZO or Ag can beused.

The sealing layer 9 is not particularly limited as long as it has a highability to shield moisture or a gas component. A film formed of aninorganic material generally known to have high moisture barrierproperty and high gas barrier property (which may hereinafter beabbreviated as “inorganic film”) can be used. In addition, the sealinglayer 9 may be obtained by laminating two or more kinds of filmsdifferent from each other in composition. The sealing layer may beconstituted by laminating an inorganic film and an organic filmdepending on properties requested of the sealing layer. However, it isnot desirable that an organic film be formed at a position B where theorganic light emitting apparatus is to be divided because the filmserves as a propagation path for moisture or a gas component.

The thickness of the sealing layer 9 is not particularly limited as longas shielding performance against moisture or a gas component can besecured. The thickness is desirably 0.5 μm or more in order thatsufficient sealing performance may be obtained, specifically, thesmoothness of the surface of the second electrode 7 may be secured, anddirt adhering to the surface may be covered.

The inorganic film for use in the sealing layer 9 of the presentinvention can be formed by, for example, plasma CVD. When the excitationfrequency of plasma CVD to be used is in a VHF band ranging from 30 MHzto 100 MHz, the ion impact of plasma can be weakened, and thermal damageto an organic EL device can be suppressed. At the same time, a goodinorganic sealing layer can be realized, which: is dense and free of anydefect; favorably covers an inclined plane or irregularities; shows highmoisture resistance; and has a low stress. The inorganic film desirablyhas a hydrogen concentration of 12 to 32 atomic % with respect to thetotal number of silicon, nitrogen, hydrogen, and oxygen atoms. In suchcase, the inorganic film favorably adheres to an organic sealing layeras a base layer, favorably covers irregularities, is effective inalleviating a thermal stress, and has an enormous effect on atemperature increase due to light emission by an organic EL device. Ahydrogen concentration of 17 to 28 atomic % is additionally effective.

An organic light emitting apparatus formed of the sealing layer 9provided with such hydrogen concentration gradient as described abovecan not only show high moisture resisting performance but also suppressthe reflection of light caused by the lamination of films different fromeach other in reflectivity to improve a light transmittance.

FIGS. 7A to 7D each illustrate an example of a method of producing anorganic light emitting apparatus according to the present invention.

The stack layer 6 and the second electrode 7 are formed on a substrateon which a three-dimensional portion A having a concave structure isformed (FIG. 7A). Subsequently, the sealing layer 9 is formed, whereby araw material substance is adsorbed to and deposited on the substrate sothat film formation proceeds. As a result, a crack or a film qualitydiscontinuous region is generated in a portion of the three-dimensionalportion A at the position where the deposition rate of the substance isdiscontinuous (FIG. 7B). In the crack or film quality discontinuousregion of the sealing layer 9, the sealing layer 9 can be easily dividedby an external impact such as an external force, heat, or anelectromagnetic wave without causing large damage such as peeling or acrack to the sealing layer 9. In addition, the division surface of thesealing layer 9 has high moisture resisting performance, and hence hassuch high shielding performance that moisture or a gas component isprevented from infiltrating from the position where the sealing layer 9is divided. Next, the sealing layer 9 and the substrate are divided inthe direction parallel to the three-dimensional portion A at a divisionposition B on or outside the three-dimensional portion A (FIG. 7C).Although damage in association with the division is generated in thesealing layer 9, the peeling and cracking of the sealing layer 9 areheld back by the crack or film quality discontinuous region of thesealing layer 9 at the position where the three-dimensional portion A isformed. As a result, damage due to the division can be prevented frompropagating through the sealing layer 9 on a display region side withrespect to the three-dimensional portion A (FIG. 7D).

It should be noted that, in the production of an organic light emittingapparatus, from the viewpoint of a reduction in production cost, pluralorganic light emitting apparatuses are formed on one substrate so thatthe plural organic light emitting apparatuses are simultaneously formed,and then each organic light emitting apparatus is divided. FIGS. 8A and8B each illustrate an example of the position where eachthree-dimensional portion A is formed upon placement of plural organiclight emitting apparatuses on a substrate.

FIG. 8A illustrates an example in which three-dimensional portions Aeach having a concave structure are formed on both sides of the divisionposition B. In this case, the substrate is divided at the divisionposition B in the direction parallel to each three-dimensional portionA. Although a crack and peeling are generated in the sealing layer 9 atthe division position B, the peeling and cracking of the sealing layer 9are held back by the crack or film quality discontinuous region of thesealing layer 9 at the position where each three-dimensional portion Ais formed. As a result, damage due to the division does not propagatethrough the sealing layer 9 on a display region side. In FIG. 8B, athree-dimensional portion A having a concave structure is formed so asto straddle the division position B. Similarly, the peeling and crackingof the sealing layer 9 generated at the division position B are heldback at the position where the three-dimensional portion A is formed. Asa result, damage due to the division does not propagate through thesealing layer 9 on a display region side.

As described above, plural three-dimensional portions A can be formedbetween adjacent organic light emitting apparatuses. In this case, thesealing layer 9 may be divided at an arbitrary position as long as it isdivided at a position outside the three-dimensional portion A closest toa display region. In other words, at least one three-dimensional portionA must be formed between the position where the sealing layer 9 isdivided and the display region.

Each of those three-dimensional portions A may be formed by an arbitrarymethod by using an arbitrary material as long as a desired structure canbe realized. However, the addition of a material and a process only forforming each three-dimensional portion A leads to: an increase in costof an organic light emitting apparatus; and a reduction in productionyield. In view of the foregoing, each three-dimensional portion isdesirably formed by using an existing constituent layer by an existingprocess.

For example, when a three-dimensional portion A having a concavestructure is produced, the portion can be formed in a TFT and theinsulating layer 3 to be formed on a substrate. More specifically,etching is performed at the position where the three-dimensional portionA is to be formed simultaneously with the provision of the insulatinglayer 3 with a contact hole, whereby the three-dimensional portion Ahaving the depth D corresponding to the thickness of the insulatinglayer 3 can be formed. When the depth D must be equal to or larger thanthe thickness of the insulating layer 3, a three-dimensional portion Ahaving the depth D whose maximum value corresponds to the totalthickness of the TFT and the insulating layer 3 can be formed bypatterning a layer for constituting the TFT in correspondence with theposition where the three-dimensional portion A is to be formed at thetime of the formation of the TFT.

A three-dimensional portion A having a convex structure can be formed byusing the leveling layer 4 and the device isolation film 8simultaneously with the formation of each layer.

It should be noted that a substrate can be divided by employing ageneral scribing approach such as scribing with a cutting edge or laserscribing. Then, the substrate is broken along a scribed division line,whereby the substrate can be divided. The application of such divisionmethod to an organic light emitting apparatus free of thethree-dimensional portion of the present invention involves a problem inthat damage to the sealing layer 9 such as the generation of a crack inthe layer or the peeling of the layer occurs at a division position.

Hereinafter, the embodiment of the present invention will be describedin more detail by way of examples.

Example 1

This example will be described with reference to FIGS. 9A and 9B. FIG.9A is a sectional view schematically illustrating a part taken out of anevaluation sample, and FIG. 9B is a top view schematically illustratingthe part.

In this example, the evaluation sample was produced as illustrated ineach of FIGS. 9A and 9B, and was evaluated for the presence or absenceof the infiltration of moisture from a division position on the basis ofa change in transmittance due to Ca corrosion. The transmittance of a Cafilm changes as a result of a reaction between the Ca film and water oroxygen.

A three-dimensional portion A having a height of 0.5 μm, a width of 1μm, and a taper angle of 55° was formed in a line shape on a substrateobtained by forming an insulating layer on a glass base material. Next,a Ca film 13 having a thickness of 1,000 Å was formed by vapordeposition partially at the central portion of the substrate at theposition distant from the three-dimensional portion A by 0.2 mm.Subsequently, a silicon nitride film having a thickness of 5 μm wasformed by VHF plasma CVD so as to cover the three-dimensional portion Aand the Ca film 13, whereby the sealing layer 9 was formed. A processcommencing on the loading of the substrate and ending on the formationof the sealing layer 9 was performed in a vacuum.

Next, the substrate was scribed from the side of the sealing layer 9with a highly permeable hole cutting blade at the position distant froman end of the Ca film by 0.3 mm and from the three-dimensional portion Aby 0.1 mm, whereby the evaluation sample was produced.

The division position of the sample of this example was observed with anSEM. As a result, the occurrence of the peeling and cracking of thesealing layer 9 was observed at the division position B. However, thepeeling and cracking of the sealing layer 9 were held back at theposition of the three-dimensional portion A, so none of peeling and acrack was observed in the sealing layer 9 on the side of the Ca film.

The evaluation sample of this example was left in a thermo-hygrostathaving a temperature of 60° C. and a relative humidity of 90% RH. Aftera lapse of 1,000 hours from the leaving, the transmittance of the Cafilm was measured, but showed no change.

Comparative Example 1

This comparative example will be described with reference to FIG. 10.FIG. 10 is a sectional view schematically illustrating a portion takenout of an evaluation sample.

In this comparative example, the evaluation sample was produced asillustrated in FIG. 10, and was evaluated for the presence or absence ofthe infiltration of moisture from a division position on the basis of achange in transmittance due to Ca corrosion.

The evaluation sample of this comparative example was produced by thesame process as that of Example 1 except that the three-dimensionalportion A was not formed. The substrate 1 was divided from the side ofthe sealing layer 9 at the position distant from an end of the Ca filmby 0.3 mm.

The division position of the sample of this comparative example wasobserved with an SEM. As a result, the occurrence of the peeling andcracking of the sealing layer 9 was observed. Damage to the sealinglayer 9 due to the division occurred in the range of 0.5 mm or less fromthe division position.

The evaluation sample of this comparative example was left in athermo-hygrostat having a temperature of 60° C. and a relative humidityof 90% RH. After a lapse of 1,000 hours from the leaving, the Ca filmwas corroded in a direction originating from the division position, anda reduction in transmittance was observed over a region of about 25 mm.

Comparative Example 2

In this comparative example, an evaluation sample was produced asillustrated in FIG. 10, and was evaluated for the presence or absence ofthe infiltration of moisture from a division position on the basis of achange in transmittance due to Ca corrosion.

The evaluation sample of this comparative example was produced by thesame process as that of Example 1 except that the three-dimensionalportion A was not formed. The substrate 1 was divided from the side ofthe substrate 1 at the position distant from an end of the Ca film by0.3 mm.

The division position of the sample of this comparative example wasobserved with an SEM. As a result, the occurrence of the peeling of thesealing layer 9 was observed. Damage to the sealing layer 9 due to thedivision occurred in the range of 0.3 mm or less from the divisionposition.

The evaluation sample of this comparative example was left in athermo-hygrostat having a temperature of 60° C. and a relative humidityof 90% RH. After a lapse of 1,000 hours from the leaving, the Ca filmwas corroded in a direction originating from the division position, anda reduction in transmittance was observed over a region of about 15 mm.

Example 2

This example will be described with reference to FIGS. 1A, 2 and 8A.

In this example, an organic light emitting apparatus illustrated in FIG.1A was produced, and was evaluated for light emitting property.

In this example, organic light emitting apparatuses each having theconstitution illustrated in FIG. 1A were formed on a large substrate soas to be adjacent to each other. Each organic light emitting apparatuswas divided after the formation of the sealing layer 9. As illustratedin FIG. 2, the three-dimensional portions A were formed between adjacentorganic light emitting apparatuses on two sides except the side on whicha power source and the signal supply pad 14 were formed and a sideopposed to the side.

As illustrated in FIG. 8A, three three-dimensional portions A eachhaving a concave structure with a depth of 0.5 μm, a width of 5 μm, anda taper angle of 60° were formed from a position distant from thedivision position B by 0.1 mm toward a display region side at a pitch of10 μm so as to be symmetric with respect to the division position B.

The organic light emitting apparatus of this example was produced asdescribed below. The layer 2 for constituting a TFT, the insulatinglayer 3, and the organic leveling layer 4 were sequentially formed onthe glass base material 1, whereby a substrate was produced. Next, acontact hole between the first electrode 5 to be formed on the substrateand the layer 2 for constituting a TFT was formed. The above-mentionedthree-dimensional portions A were formed in the insulating layer 3simultaneously with the formation of the contact hole. Subsequently, thefirst electrode 5 was formed, and the device isolation film 8 made ofpolyimide was formed on the periphery of the first electrode 5 toinsulate the electrode. The stack layer 6 made ofFL03/DpyFL+sDTAB2/DFPH1/DFPH1+Cs₂CO₃ was deposited from the vapor ontothe substrate, whereby the stack layer 6 obtained by laminating a holetransporting layer, a light emitting layer, an electron transportinglayer, and an electron injecting layer in the stated order was formed.The second electrode 7 made of ITO and having a thickness of 60 nm wasformed by sputtering on the laminate, whereby a pixel was formed.Further, a silicon nitride film having a thickness of 5 μm was formed byVHF plasma CVD so as to cover the organic leveling layer 4, the firstelectrode 5, the stack layer 6, the second electrode 7, the deviceisolation film 8, the adhesive 10, and the three-dimensional portions A,whereby the sealing layer 9 was formed. A process commencing on theloading of the glass base material 1 and ending on the formation of thesealing layer 9 was performed in a vacuum.

Next, the substrate was scribed from the side of the sealing layer 9with a highly permeable hole cutting blade at the division position B,whereby each organic light emitting apparatus was divided. Subsequently,the circular polarizer 11 was bonded to the sealing layer 9 of eachorganic light emitting apparatus by using the adhesive 10, whereby theorganic light emitting apparatus illustrated in FIG. 1A was produced.

The division position of the organic light emitting apparatus of thisexample was observed with an optical microscope and an SEM. As a result,a crack and peeling were observed in the sealing layer 9. However, noneof a crack and peeling was observed in the sealing layer 9 on thedisplay region side with respect to the three-dimensional portion Aclosest to the display region.

The organic light emitting apparatus of this example was left in athermo-hygrostat having a temperature of 60° C. and a relative humidityof 90% RH. After a lapse of hours from the leaving, the apparatus wasevaluated for V-I characteristics and luminance, but the deteriorationof the V-I characteristics and of the luminance was not observed. Inaddition, none of a luminance change and a dark spot having a diameter Φof 1 μm or more occurred from the outer peripheral region of the organiclight emitting apparatus. In addition, none of luminance deteriorationand a dark spot having a diameter Φ of 1 μm or more occurred from theperiphery of the pixel.

Example 3

This example will be described with reference to FIGS. 1A, 2 and 8B.

In this example, an organic light emitting apparatus similar to that ofExample 2 was produced, and was evaluated for light emitting property;provided that, in this example, as illustrated in FIG. 8B, a concavestructure having a depth of 0.5 μm, a width of 100 μm, and a taper angleof 60° was formed as a three-dimensional portion A so as to straddle thedivision position B, and, furthermore, three three-dimensional portionsA each having a depth of 0.5 μm, a width of 5 μm, and a taper angle of60° were formed from an end of the concave structure toward a displayregion side at a variable pitch of 30 μm, 20 μm, and 10 μm.

The division position of the organic light emitting apparatus of thisexample was observed with an optical microscope and an SEM. As a result,a crack and peeling were observed in the sealing layer 9. However, noneof a crack and peeling was observed in the sealing layer 9 on thedisplay region side with respect to the three-dimensional portion Aclosest to the display region.

The organic light emitting apparatus of this example was left in athermo-hygrostat having a temperature of 60° C. and a relative humidityof 90% RH. After a lapse of 1,000 hours from the leaving, the apparatuswas evaluated for V-I characteristics and luminance, but thedeterioration of the V-I characteristics and of the luminance was notobserved. In addition, none of a luminance change and a dark spot havinga diameter Φ of 1 μm or more occurred from the outer peripheral regionof the organic light emitting apparatus. In addition, none of luminancedeterioration and a dark spot having a diameter Φ of 1 μm or moreoccurred from the periphery of the pixel.

The organic light emitting apparatus according to the present inventionis excellent in ability to shield moisture and a gas component.Therefore, the apparatus can be utilized in, for example, the displayapparatus of a mobile instrument such as the monitor of a digital cameraor of a digital video camera which: is assumed to be used in a widerange of temperatures or of humidity; and requires high environmentalresistance.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application Nos.2006-087310, filed Mar. 28, 2006, and 2007-026707, filed Feb. 6, 2007,which are hereby incorporated by reference herein in their entirety.

1. An organic light emitting apparatus obtained by dividing pluralorganic light emitting apparatuses that are integrally formed, theorganic light emitting apparatus comprising: a substrate having at leasta base material, the substrate having sides formed by dividing thesubstrate at its ends, and the substrate having three-dimensionalportions formed on its surface along the sides; an organic lightemitting device formed on the substrate, the organic light emittingdevice having a first electrode, an organic light emitting layer, and asecond electrode in the stated order on the substrate; and an inorganicsealing layer formed to cover an upper portion of the organic lightemitting device and the surface of the substrate and to extend towardthe three-dimensional portions.
 2. The organic light emitting apparatusaccording to claim 1, wherein the number of the three-dimensionalportions to be formed is two or more.
 3. The organic light emittingapparatus according to claim 1, wherein adjacent three-dimensionalportions of the three-dimensional portions are different from each otherin at least one of shape and pitch.
 4. The organic light emittingapparatus according to claim 1, wherein each of the three-dimensionalportions has one of a height of 0.1 μm or more and a depth of 0.1 μm ormore.
 5. The organic light emitting apparatus according to claim 1,wherein a height or a depth of each of the three-dimensional portions isone hundredth or more of a thickness of the inorganic sealing layer. 6.A method of producing an organic light emitting apparatus, the organiclight emitting apparatus having a substrate, an organic light emittingdevice having a first electrode, an organic light emitting layer, and asecond electrode formed in the stated order on the substrate, and aninorganic sealing layer formed to cover an upper portion of the organiclight emitting device and a surface of the substrate and to extendtoward an end of the substrate, the method comprising the steps of:forming the organic light emitting device having the first electrode,the organic light emitting layer, and the second electrode in the statedorder on the substrate; forming a three-dimensional portion along adivision line set in advance on the surface of the substrate; formingthe inorganic sealing layer in the division line from above the secondelectrode so that the inorganic sealing layer straddles thethree-dimensional portion; and dividing the substrate and inorganicsealing layer along the division line.
 7. The method of producing anorganic light emitting apparatus according to claim 6, wherein thedividing step has a step of scribing the inorganic sealing layer alongthe division line and a step of breaking the substrate and inorganicsealing layer along the scribed division line.
 8. The method ofproducing an organic light emitting apparatus according to claim 6,wherein: the step of forming the organic light emitting device comprisesa step of forming plural organic light emitting devices on thesubstrate; and the division line is present between adjacent devices ofthe organic light emitting devices.
 9. The method of producing anorganic light emitting apparatus according to claim 6, wherein the stepof forming the three-dimensional portion comprises an etching step.